On Thursday, July 11, 2013 9:08:02 AM UTC-4, snipped-for-privacy@gmail.com wrote: > I have a GSM controller that can switch a relay for a minimum time of 1 sec, however I need a 300ms pulse. I am looking for a circuit that can take the 1 sec relay output (as an input) and give me a 300ms output for a second relay.
If this were a system with DC power supply, and logic-level output, it's easy. If it's an AC-power (mains) system, things get trickier: the best might be an AC timed relay connected in series, that turns OFF after 300 msec, and resets when power is removed.
It matters a lot what kind of power is available (and what the nature of the intended load is).